Wednesday, June 04, 2008

What to do about Micrometastases?

“When someone has a very small amount of tumor, what is their actual risk?” asked Dr. Hiram S. Cody III of the Memorial Sloan-Kettering Cancer Center in New York. A tiny bit of cancer could mean that a tumor is going to reignite. Or it could mean very little.

The presence of these so-called micrometastases, and other wisps of tumor too small to count as full-fledged metastases, has been documented in lymph nodes for decades. But only with the popularity of sentinel node testing has the question of micrometastasis entered everyday medical practice.

“Because they are looking at fewer nodes, they can look more carefully,” said Brenda K. Edwards, associate director for surveillance research at the National Cancer Institute.

Dr. Edwards and her colleagues recently found that diagnoses of breast cancer with micrometastatic lymph-node involvement began to increase markedly after 1997 and that it shows no signs of leveling off.

So, what does one do about these findings? I suppose these are potentially false positives, but I feel like my bias is still towards treatment. The article notes that some women experience arm/axillary tightness after such biopsies, but that seems a small price to pay to reduce the risk of metastatic breast cancer. I think the question should be more explicitly framed as how to treat these findings of micrometastases, instead of the implicit "Should we treat them, or not?" Perhaps I need to read more about this, but it seems like not treating a positive finding is a dangerous road to follow without some very, very solid data.